The principal Investigator has recently codirected (with Philip E. Converse) a major national survey of trends in the psychological well-being of the national population. A total of 3,692 interviews were taken in July-August 1978 from a probability sample of Americans 19 years and older living in private households. This survey follows a similar study completed by the same applicant and his Associates (Converse and Willard L. Rodgers) in 1971, published in The Quality of American Life (Russell Sage, 1976). A panel of 702 of the 1971 respondents were reinterviewed in 1978. A descriptive statement of the general trend data from 1971 to 1978 is in press (Campbell, McGraw-Hill). This application is for continued analysis and publication from this unique data set, concentrating on the relation of social support to psychological well-being through the life span, with particular emphasis on people 65 years old and older. The analysis proposes to place major emphasis on comparing specified age cohorts from the 1971 and 1978 surveys and on identifying the conditions of stability and change in the panel of 702 individuals interviewed in both 1971 and 1978. The central hypothesis guiding the analysis assumes that social support contributes to psychological well-being and is particularly effective in moderating life stresses which might be expected to reduce feelings of well-being.